September 25: ORD

Today is September 25th. It's the 269th day of the year. 97 days remain. It's week 39 of the year.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between November 1978 and last year. Observations have been official at O'Hare since Thursday, January 17, 1980.

According to the National Climatic Data Center (NCDC), the normal high is 71 and the normal low is 50. The 29-year averages are 71 and 48.

On the warm side, in 1986 the high was 88 with a low of 68. Last year the high was 85 with a low of 63. Other warm highs were 81 in both 1990 and 1998. It was 80 in both 1979 and 1999. Another warm low was 67 in 2005. The record high of 90 was set in 1933 and the record warmest low of 72 was set in 1920. Although the 70s have 11 occurrences over the last 29 years, the three other categories are nearly even: the 50s with five, the 60s with seven and the 80s with six.

The largest spread of 37 degrees happened in 1999 as the high was 80 with a low of 43. There was a 34 degree spread in 1984 with a high of 74 and low of 40. The spread was 32 degrees in 1988 (77/45). Two spreads of 31 degrees: the first in 1989 (70/39) and then in 2002 (74/43). A 30 degree spread in 1998 (81/51). A small spread of three degrees in 1983 (58/55) and five degrees in 1982 (52/47).

On the cool side, in 1985 the high was 58 with a low of 35. In 2000 the high was 55 with a low of 43. In 2001 the high was 58 with a low of 40. In 1982 the high was 52 with a low of 47. Another cool high was 58 in 1983. Other cool lows were 39 in 1989, 40 in 1984 and 41 in both 1991 and 1996. The record low of 30 was set in 1942 and the record coolest high of 46 was set the same year (1942). 15 of the last 29 lows have been 40s and nine have been 50s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:16 and sunrise is at 6:44. Sunset is at 18:44 and twilight ends at 19:12. Twilight begins tomorrow at 6:17 and sunrise is at 6:45. There's a total of 12 hours of daylight today and 12 hours, 56 minutes between twilights. The moon is waning crescent. Illumination was 18% at midnight, will be 14% at noon and 11% at midnight tonight. Moonrise was at 2:32 this morning. Moonset is at 16:59 this afternoon and moonrise is at 3:45 tomorrow morning. Moonlight time is 14 hours, 27 minutes today. The autumnal equinox was three days ago at 10:44.

The following events are all 18 days away on October 13th: Columbus Day, my parents' 46th wedding anniversary and a brother-in-law, Buddy, will be turning 33. -Bernie-